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Background: RecQ‐mediated genome instability 2 (RMI2) maintains genome stability by promoting DNA damage repair. It has been reported to accelerate the progression of several tumors. However, the functional mechanism of RMI2 in breast cancer remains unclear. Methods: Gene expression profiles were obtained from TCGA, GTEx, and GEO databases. The expression of RMI2 and its prognostic value in breast cancer was explored. In addition, we calculated pooled standardized mean deviation (SMD) and performed a summary receiver operating characteristic (sROC) curve analysis to further determine RMI2 expression status and diagnostic significance. The functions and related signaling pathways were investigated based on GO and KEGG analyses. The PPI network was constructed by combining the STRING database and Cytoscape software. Subsequently, in vitro assays were conducted to detect the effect of RMI2 on the proliferation and migration of breast cancer cells. Results: The expression of RMI2 was markedly upregulated in breast cancer tissues relative to that in normal tissues. Moreover, pooled SMD further confirmed the overexpression of RMI2 in breast cancer (SMD = 1.29, 95% confidence interval (CI): 1.18–1.41, p = 0.000). The sROC curve analysis result suggested that RMI2 had a relatively high diagnostic ability in breast cancer (AUC = 0.87, 95% CI: 0.84–0.90). High RMI2 expression was associated with poor prognosis. GO and KEGG analyses revealed that RMI2 was closely related to cell adhesion, various enzyme activities, and PI3K/AKT signaling pathway. PPI analysis showed that RMI2 had interactions with proteins involved in DNA damage repair. knockdown of RMI2 remarkably inhibited the proliferation and migration of breast cancer cells, while overexpression of RMI2 exerted the opposite effects. Furthermore, we identified that RMI2 accelerates the proliferation and migration of breast cancer cells via activation of the PI3K/AKT pathway. Conclusion: The results suggest that RMI2 is a potential diagnostic and prognostic biomarker associated with cell proliferation and migration, and may be used as a novel therapeutic target for breast cancer in the future. [ABSTRACT FROM AUTHOR]

Molecular annotated patient-derived xenograft (PDX) models are useful for the preclinical investigation of anticancer drugs and individualized anticancer therapy. We established 23 PDXs from 88 surgical specimens of lung cancer patients and determined gene mutations in these PDXs and their paired primary tumors by ultradeep exome sequencing on 202 cancer-related genes. The numbers of primary tumors with deleterious mutations in TP53, KRAS, PI3KCA, ALK, STK11, and EGFR were 43.5%, 21.7%, 17.4%, 17.4%, 13.0%, and 8.7%, respectively. Other genes with deleterious mutations in ≥3 (13.0%) primary tumors were MLL3, SETD2, ATM, ARID1A, CRIPAK, HGF, BAI3, EP300, KDR, PDGRRA and RUNX1 . Of 315 mutations detected in the primary tumors, 293 (93%) were also detected in their corresponding PDXs, indicating that PDXs have the capacity to recapitulate the mutations in primary tumors. Nevertheless, a substantial number of mutations had higher allele frequencies in the PDXs than in the primary tumors, or were not detectable in the primary tumor, suggesting the possibility of tumor cell enrichment in PDXs or heterogeneity in the primary tumors. The molecularly annotated PDXs generated from this study could be useful for future translational studies. [ABSTRACT FROM AUTHOR]

In this paper Polyacene quinone radical (PAQR) polymers were synthesized by the step-growth condensation of aromatic hydrocarbon derivatives reacting with pyromellitic anhydirde via a solvothermal method at 180°C for 2 h, using zinc chloride as catalyst and cyclohexane as solvent. The effects of solvents and different aromatic hydrocarbons on the synthesis and morphology of PAQR polymers were investigated. [ABSTRACT FROM AUTHOR]

Abstract: Silica-coated copper nanoparticles were synthesized by coating copper nanoparticles with a silica shell through microemulsion. The copper nanoparticles are 30–40nm in diameter and the silica coating is 10nm in thickness. After coating, copper nanoparticles were encapsulated in a silica matrix. These particles were used as a catalyst for the growth of carbon nanofibers in a tubular furnace. It is found that carbon nanofibers are mirror-symmetric growth and 100nm in diameter. During growth, the copper nanoparticles moved out of the silica. As the experiment progressed, the interplanar spacing of copper (220) increased from 0.1288nm to 0.1306nm indicating that (220) plane exhibited high catalytic activity. The out-of-sync growth of different faces provides new evidence for the research of growth mode in carbon nanofibers. [Copyright &y& Elsevier]

Abstract: Magnetic composites of nickel-coated carbon nanofibers have been successfully fabricated by employing a simple microwave-assisted procedure. The scanning electron microscopy images show that a complete and uniform nickel coating with mean size of 25nm could be deposited on carbon fibers. Magnetization curves demonstrate that the prepared composites are ferromagnetic and that the coercivity is 96Oe. The magnetic carbon nanofibers can be aligned as a long-chain structure in an external magnetic field. [Copyright &y& Elsevier]

Abstract: Lead tungstate (PbWO4) microcrystals with different morphologies, such as tetragonal flowerlike, amygdaloidal, and multiple-lamellar, have been successfully synthesized via a simple microwave-assisted method. Various factors, such as the pH value and the concentration of the cetyltrimethylammonium bromide (CTAB), play an important role in the morphological control of PbWO4 microcrystals. The products were characterized by the techniques of powder X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. The possible formation mechanisms of PbWO4 samples of various morphologies were discussed. The luminescence properties of the final products were investigated and the as-prepared PbWO4 microcrystals showed special room-temperature photoluminescence intensity compared to the solid structures. [Copyright &y& Elsevier]

Abstract: Lead tungstate (PbWO4) microcrystals with different morphologies, such as tetragonal sheet-like, multiwall-like, quasi octahedron-like, and flower-like, have been successfully synthesized for the first time via a facile microwave-assisted method. The concentration of cetyltrimethylammonium and the reaction time were found to play an important role in the morphological control of resulting PbWO4 microcrystals. The products were characterized by the techniques of powder X-ray diffraction pattern and field-emission scanning electron microscopy. A possible process contributed to the formation of the well-fined PbWO4 microcrystals was discussed. The PbWO4 microcrystals were found to display a strong room temperature luminescence with intensity depending on their shape. [Copyright &y& Elsevier]

Crosslinked polyethylene (XLPE) is an important polyethylene modification material which is widely used in high-voltage direct current (HVDC) transmission systems. Low-density polyethylene (LDPE) was used as a matrix to improve the thermal and electrical properties of XLPE composites through the synergistic effect of a crosslinking agent and nanopore structure molecular sieve, TS-1. It was found that the electrical and thermal properties of the matrices were different due to the crosslinking degree and crosslinking efficiency, and the introduction of TS-1 enhanced the dielectric constants of the two matrices to 2.53 and 2.54, and the direct current (DC) resistivities were increased to 3 × 1012 and 4 × 1012 Ω·m, with the enhancement of the thermal conductivity at different temperatures. As the applied voltage increases, the DC breakdown field strength is enhanced from 318 to 363 kV/mm and 330 to 356 kV/mm. The unique nanopore structure of TS-1 itself can inhibit the injection and accumulation in the internal space of crosslinked polyethylene composites, and the pore size effect of the filler can limit the development of electron impact ionization, inhibit the electron avalanche breakdown, and improve the strength of the external applied electric field (breakdown field) that TS-1/XLPE nanocomposites can withstand. This provides a new method for the preparation of nanocomposite insulating dielectric materials for HVDC transmission systems with better performance. [ABSTRACT FROM AUTHOR]

This study focuses on in situ synthesis of ZnS nanoparticles on the surface of multiwalled carbon nanotubes. By microwave-assisted chemical reaction of Zn(Ac)2·2H2O and NaS·9H2O in glycol solution with carbon nanotubes, which were pretreated by oxidization in concentrated HNO3. Zinc sulfide crystallite densely supported on carbon nanotubes with the diameter about 1 nm. The carbon nanotubes decorated by ZnS were characterized using transmission electron microscopy and x-ray diffraction. It is found that the multi-walled carbon nanotubes can not only act as a substrate but also change the crystal structures of ZnS in the reaction. [ABSTRACT FROM AUTHOR]

Abstract: HNO3-treated multi-walled carbon nanotubes enclosed by flower-like zinc oxide particles were prepared by a microwave irradiation heating method. The product was characterized by X-ray diffraction and scanning electron microscopy. It was found that the flower-like zinc oxide grows around the multi-walled carbon nanotubes to form a floral-patterned structure. Multi-walled carbon nanotubes play a role as a template for the growth of ZnO and they can link ZnO particles together as a complex fabrication. This discovery is useful for nano-electronic applications. [Copyright &y& Elsevier]

Polypropylene (PP) receives significant interests because of environmental friendship and excellent insulation. The development of PP cables depends heavily on the semi-conductive shielding layers that match the PP insulation layers. In this paper, propylene–ethylene copolymer (POP) is used to toughen the PP-based shielding layer. The effects of POP content (40 parts, 50 parts and 60 parts) on the electrical and mechanical characteristics are investigated. Further, the interface matching characteristics and toughening mechanism of the shielding layer are explored. According to the experimental findings, owing to the growth in POP content, the distribution of carbon black (CB) particles becomes more uniform, and the surface roughness decreases from 52.7 nm to 14.7 nm. When the POP content is 60 parts, the charge injected into the insulation layer is the least, which is 0.643 × 10−7 C, and the maximum electric field distortion decreases to 11.4 kV/mm. All three POP content shielding layers maintain a low resistivity at high temperatures (110 ℃, 80 Ω·cm). Besides, as the POP content increases, the toughness of PP-based shielding layer is improved and the elongation at break of POP-60 semi-conductive shielding layer reaches 420%. This research paves a new way for the development of semi-conductive shielding layer of PP cables. [ABSTRACT FROM AUTHOR]

The semiconductive layer located between the core and insulation layer of a high-voltage DC (HVDC) cable can inhibit the accumulation of space charge in the insulation layer. This helps increasing the electric field inside the cable, thus improving the stress distribution of the electric field on the inner and outer surfaces of the insulation layer and the electrical strength of the cable. An inevitable positive temperature coefficient effect (PTC) in the semiconductor layer leads to aging failure of the insulation layer. To improve this phenomenon, the semiconductive shielding layer was modified for suppressing its PTC effect and reducing the space charge injection into the insulation layer. Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 (LATP) was prepared via a solid-phase reaction and added to a composite consisting of carbon black (CB), ethylene vinyl acetate copolymer (EVA), and low-density polyethylene (LDPE). Resistivity, thermally stimulated depolarization current (TSDC), and pulsed electroacoustic (PEA) measurements were performed on the modified sample. The results showed that when the LATP content was 4 wt%, the modification effect of the semiconductive shielding layer was most effective, the PTC effect was reduced by 11%, and the space charge injection into the insulating layer was improved significantly. [ABSTRACT FROM AUTHOR]

Ceramic composites made up of well-selected components have enriched the varieties of the metamaterials with negative electromagnetic parameters. In this work, TiN/BaTiO 3 ceramic composites were prepared with a simple dry-pressing and pressureless sintering process. Percolation was eventually determined to be the key inducements which caused the permittivity of the ceramic composites changing from positive to negative. Essentially, negative permittivity was closely related to the plasma oscillations of free electrons in percolation networks. Meanwhile, conduction mechanism of the composites varied owing to the changes in microstructure, where the percolation networks brought out pathways for electron migration and achieved high conductivity. In addition, ac impedance behavior with changes of the sign for reactance were also discussed, thus the transition from electrical capacitive to inductive for the percolative ceramic composites has been demonstrated. This work clarified the influence of percolation on the conductivity, impedance, and permittivity of ceramic composites altogether. The obtained negative permittivity composites have enormous potential in various electronic devices and electromagnetic apparatus. [ABSTRACT FROM AUTHOR]

Temperature and electric field are important factors affecting space charge accumulation in high voltage dc (HVDC) cable insulation. Charge conduction and accumulation in XLPE have been studied by correlating the polarization and depolarization processes. The experimental results indicate that the steady current of XLPE increases about 2 or 3 orders with the increasing temperature from 25 °C to 90 °C, and the stronger electric field, the less the increased amplitudes. The trap level in XLPE stressed by different electric fields and temperatures have a tiny change from 0.89 eV to 1.15 eV. Besides, there exists an inflection temperature of charge accumulation in XLPE, around 50 °C∼ 60 °C. At the room temperature, the trapped charges are difficult to release from the traps, and these homo-charges near the electrode can depress the further injection of charges. With the increase of temperature, part of trapped charges near the interface will gradually migrate towards the bulk of the material, and more charges are injected. When the temperature exceeds around 50 °C, the molecular movement is accelerated which can dramatically enhance the hopping probability of charges between the adjacent traps, and little accumulated charges are left. [ABSTRACT FROM AUTHOR]

Silicone rubber has been widely used in electric power equipment for its excellent insulation performance and weather resistance. However, the weak breakdown characteristic of silicone rubber limits its application in high-voltage grade power equipment. In this paper, the nano-modification system of silicone rubber based on a binary composite matrix of "phenyl-vinyl" was constructed. On the one hand, the benzene ring structure is introduced to improve the breakdown strength of the matrix. On the other hand, barium strontium titanate (BST) is used to improve the permittivity of composite, reducing the electric field shared by silicone rubber. The experimental results show using binary composite silicone rubber as the matrix, the appropriate amount of BST filling can greatly improve the permittivity of the composite. When the BST content is 30 wt%, the permittivity of the binary composite reaches the maximum value of 3.98, which is about 49.06% higher than that of vinyl silicone rubber. Accordingly, the electric field strength shared by silicone rubber insulation will decrease significantly. Meanwhile, the moderate amount of BST in the matrix can improve the breakdown strength. This work is an important guideline for the performance improvement of silicone rubber for high-voltage power equipment. [ABSTRACT FROM AUTHOR]

The conformational transition of cyclohexylene ring has been recognized as the secondary transition of polyesters containing this aliphatic ring structure. Previously, the stereochemistry, i.e., trans/cis ratio, has been identified as an important factor that has a significant impact on the conformational transition of the cyclohexylene ring. In this paper, we have proposed and proved the side chain effect as another important factor that plays the same role as the stereochemistry, due to the fact that the conformational transition of the ring is usually associated with the coupled motion of it with neighboring unit. Our strategy is to design and synthesize a series of polyesters with 1,4-cyclohexanedicarboxylic acid and diols with different side chains. Polyester without any side chain has the lowest secondary relaxation temperature (Tβ). Incorporation of asymmetric short side chain will result in increased Tβ, since it will reduce the coupled motion of the neighboring unit with the cyclohexylene ring during the conformational transition process, and thus reduces the flexibility of the chain and increases steric hindrance. However, further incorporation of long side chain will result in decreased Tβ because of the plasticization effect. Moreover, we also found that polyesters with low Tβ tend to have not only better impact strength, but also good ductility and elasticity. Our study enables people to take advantage of the cyclohexylene ring structure for the design and synthesis of thermoplastic and elastomer with better performance. [ABSTRACT FROM AUTHOR]

Ceramic composites with negative permittivity have attracted widespread attention during the development of novel electromagnetic metamaterials. Herein, carbon nanotubes/TiN/CaCu 3 Ti 4 O 12 (CNTs/TiN/CaCu 3 Ti 4 O 12) ternary composites were prepared, and the effects of dual fillers on the dielectric properties of the ternary composites are discussed. The electrical conductivity increased markedly, and the conduction mechanism changed owing to the percolation of the dual conductor fillers. The switching of the reactance, from negative to positive, suggests that the ternary composites underwent a capacitive-inductive transition. The dielectric permittivity was negative owing to the plasmonic state of the free electrons in the percolating conductor fillers. Regulating the electron concentration by changing the filler content or adjusting the microstructure by changing the relative content of the dual fillers proved to be an effective way to tailor the negative permittivity performance of ternary composites. In addition, conduction loss dominated the dielectric loss mechanism of the negative permittivity composites. The realization and regulation mechanism of the negative permittivity of ternary composites are clarified, shedding light on the preparation and development of negative permittivity materials for various electromagnetic applications. [ABSTRACT FROM AUTHOR]

Influence mechanism of side group types on the macroscopic electrical properties of silicone rubber (SiR) are analyzed based on the experimental comparison and the molecular simulation. The insulation properties of SiR with different side group types (vinyl, phenyl, and trifluoropropyl), as well as binary compound SiR (vinyl/phenyl and vinyl/trifluoropropyl) are compared and studied experimentally. Further, the effect of side groups on the movement of the molecular chain is analyzed by calculating the free volume, the mean square displacement (MSD), and the end distances. Then the mechanism of its influence on the macroscopic properties of SiR was studied. The experimental results indicated that the resistance and breakdown performance of the phenyl SiR surpasses both vinyl SiR and fluorosilicone rubber owing to the conjugated structure of benzene ring, which has a high electron affinity and reduces free charges and carrier migration rate. Besides, when 10wt% phenyl SiR was mixed into vinyl SiR, the resistivity increased by one order of magnitude, and the breakdown field strength increased by about 8%. In the aspect of dielectric properties, the fluorosilicone rubber is more qualified than the vinyl SiR and the phenyl SiR due to the addition of trifluoropropyl as a polar group to the non-polar dielectric SiR to boost its dielectric constant and dielectric loss. The molecular simulation results indicated that the SiR containing phenyl has a tiny free volume and weak molecular chain movement, the fluorosilicone rubber has the strongest molecular chain movement. The work has important guiding significance for improving and modifying SiR in power equipment. [ABSTRACT FROM AUTHOR]

N/P dual-doped three-dimensional porous carbon was synthesized via nano-CaCO 3 template-assistant carbonization of intumescent flame retardants (IFRs) precursor. [Display omitted] Heteroatom-doped three-dimensional (3D) porous carbons possess great potential as promising electrodes for high-performance supercapacitors. Inspired by the inherent features of intumescent flame retardants (IFRs) with universal availability, rich heteroatoms and easy thermal-carbonization to form porous carbons, herein we proposed a self-assembling and template self-activation strategy to produce N/P dual-doped 3D porous carbons by nano-CaCO 3 template-assistant carbonization of IFRs. The IFRs-derived carbon exhibited large specific surface area, well-balanced hierarchical porosity, high N/P contents and interconnected 3D skeleton. Benefitting from these predominant characteristics on structure and composition, the assembled supercapacitive electrodes exhibited outstanding electrochemical performances. In three-electrode 6 M KOH system, it delivered high specific capacitances of 407 F g−1 at 0.5 A g−1, and good rate capability of 61.2% capacitance retention at 20 A g−1. In two-electrode organic EMIMBF 4 /PC system, its displayed high energy density of 62.8 Wh kg−1 at a power density of 748.4 W kg−1, meanwhile it had excellent cycling stability with 84.7% capacitance retention after 10,000 cycles. To our best knowledge, it is the first example to synthesize porous carbon from IFRs precursor. Thus, the current work paved a novel and low-cost way for the production of high-valued carbon material, and expanded its application for high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

A method of space charge suppression for high-voltage direct current (HVDC) cable is proposed by the modification of the semiconductive layer. In this work, the magnetic particle of SrFe12O19 is used to modify the semiconductive shielding layer, and the effect of SrFe12O19 orientation on the charge accumulation of the insulation layer has been studied. First, the semiconductive composite with different SrFe12O19 contents is prepared and their physicochemical properties are characterized. Second, the effect of the SrFe12O19 orientation in the semiconductive layer and the doping contents on the charge accumulation in the insulation layer is analyzed by measuring the resistivity and space charge. The experimental results show that a certain amount of SrFe12O19 (≤10 wt%) can effectively reduce the positive temperature coefficient (PTC) effect, and the orientation can more effectively reduce the space charge injection from the metal wire core to the insulation layer, thus inhibiting the charge accumulation in the insulation layer. While when the content of magnetic particles is high, it will promote the second injection of the charges, leading to an increase of the charge accumulation. The work provides a new idea for space charge suppression of HVDC cable insulation layer. [ABSTRACT FROM AUTHOR]

To fully understand the distribution network cable accessories’ moisture fault, the variation in insulation parameters of the cable main insulation of cross-linked polyethylene (XLPE) and the cable accessory reinforced insulation of silicone rubber (SIR) under different moisture conditions are studied experimentally. Furthermore, the effects of typical moisture defect forms and moisture positions on electric field distributions are studied by establishing the interface defect model. The experimental results show that the insulation properties of XLPE after water immersion are more seriously reduced than SIR. The resistivity of XLPE and SIR specimens decreases significantly with the increase in moisture time, decreasing by 90.3% and 48.3% after 720 h, respectively. The relative dielectric constants of the two kinds of specimens increase with different degrees after moisture, increasing by 5.16% and 7.83%, respectively, and the breakdown strength decreases by 18.3% and 13.1% after 720 h, respectively. The simulated results show that the moisture form and position have a great influence on electric field distribution. The electric field distortion caused by water trees’ defect is the most serious, followed by water film defects and water droplet defects. Besides, for different types of moisture defects, the position of the maximum distortion electric field is different. [ABSTRACT FROM AUTHOR]

With the purpose to turn wastes into wealth and develop renewable energy, much effort has been focused on converting biowastes into porous carbons and exploring their application for supercapacitors. In this study, inspired by natural porous structure of biomass and small size of Sn nanoparticles, a one-step strategy was developed to convert waste wolfberry fruits into porous carbons by SnCl 2. The as-fabricated carbon exhibited large specific surface area of 1423 m2 g−1 and hierarchical porosity with total pore volume of 1.36 cm3 g−1. Meanwhile, the newly produced SnCl 2 with more than 95% recovery rate was reused as catalyst. Moreover, the porous carbon was applied for supercapacitive electrode. In three-electrode 6 M KOH system, it displayed outstanding capacitance of 365 F/g at 0.2 A g−1, good rate capability of 75% capacitance retention at 20 A g−1 and excellent cycling stability of 96.4% capacitance retention after 10000 cycles. In two-electrode 1 M Li 2 SO 4 system, its energy density reached 23.2 Wh kg−1 at a power density of 225 W kg−1. The current work provided a facile and low-cost method to recycle renewable biowastes into high-valued carbon material, and further expanded its application for high-performance energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] One pot of a simple solvothermal method has been used for the preparation of different polyacene quinone radical (PAQR) polymers. [•] The presented PAQR polymers with different conductivity are successfully obtained. [•] PAQR polymers exibit smart electrorheological behavior. [ABSTRACT FROM AUTHOR]

With increasing development of chip and circuit integration, the requirements regarding the viscosity, activity, and thermomechanical properties of underfill are becoming increasingly stringent. However, common low-viscosity resins are often obtained with poor thermal and thermomechanical properties. In this study, natural renewable pyrogallol was used as a raw material and preparedto prepare a high-performance polyphenol epoxy resin monomer named E3PG (pyrogallol triglycidyl ether) through employing a combination of epichlorohydrin and olefin epoxidation methods for the first time. At 25°C, the viscosity of E3PG was only 210 cps, indicating excellent processability. Compared with traditional epoxy resin (E51), E3PG has a lower activation energy, and more importantly, exhibits excellent thermomechanical properties after curing; its glass transition temperature (T g) reaches 164°C, and its storage modulus (E′) reaches 3500 MPa at 25°C. In this study, an epoxy resin monomer with excellent properties was successfully prepared using renewable polyphenols as raw materials, providing a unique and novel approach for the synthesis of epoxy resin monomers. [Display omitted] • High purity of pyrogallol triglycidyl ether (E3PG) was successfully prepared. • E3PG exhibits higher curing activity than traditional resin (E51). • E3PG has a very low viscosity of 210 cps at 25°C. • The curing kinetic equations were visualized and α- T -t were drawn. • The T g of E3PG/MeTHPA cured was as high as 164°C. [ABSTRACT FROM AUTHOR]

• 2 wt% Li(Ni 0.9 Co 0.05 Mn 0.05)O 2 (NCM) can reduce the PTC effect by 11%. • The synergistic effect of NCM and carbon black constructs denser conductive networks. • 2 wt% NCM can inhibit the injection of space charge more effectively. The conductive mechanism of the semiconductor shielding layer between the conductive core and the insulation layer of high-voltage direct current (HVDC) cables includes tunneling and over-diffusion theories; however, the ethylene vinyl acetate copolymer (EVA) matrix in the semi-conductive composite material expands when heated, leading to a break in the carbon black (CB) conductive networks, which results in an increase in resistivity and the formation of the positive temperature coefficient (PTC) effect. The addition of materials with negative temperature coefficient (NTC) properties can weaken the PTC effect while absorbing some free electrons to enhance the suppression of space charge injection into the insulating layer. Li(Ni 0.9 Co 0.05 Mn 0.05)O 2 (NCM) was prepared by sol–gel method, which was melted and mixed with low-density polyethylene (LDPE), EVA, and CB, and pressed and molded to obtain modified semi-conductive composites. The semiconducting composites were measured by resistivity, thermal stimulation depolarizing current method (TSDC), and pulsed electroacoustic method (PEA). The results showed that the composites had the best performance when the NCM doping was 2 wt%. [ABSTRACT FROM AUTHOR]

Carbon-encapsulated Fe nanoparticles were synthesized by a modified arc plasma method using methane and starch as carbon sources, respectively. The particles were characterized in detail by transmission electron microscope and X-ray powder diffraction. They are somewhat spherical in shape and the coating layers of the two sample types are composed of amorphous carbon. Magnetic measurements using a vibrating sample magnetometer demonstrate that the prepared composites have different magnetic properties. [ABSTRACT FROM AUTHOR]

In this paper, a novel H 2 Ti 2 O 5 @MoS 2 @SiO 2 ternary composite material was prepared by a combination of dual hydrothermal method and controlled hydrolysis method, in which H 2 Ti 2 O 5 nanotubes are tightly combined with hierarchical molybdenum disulfide, and the unique structure of titanate nano whiskers, including the loosely bound alkali metal ions between the titanate layers with high dielectric constant and the large aspect ratio, which induce active response to the electric field. Flower-like molybdenum disulfide provides electrical conductivity, and silicon dioxide as a insulative coating layer can suppress excessive the electrical conductivity of the two-dimensional material. The morphological evolution was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results of showed that the sheet-shaped molybdenum disulfide coated with curved H 2 Ti 2 O 5 nanotubes showed a honeycomb structure with uniform size. Silicon oxide acts as a cladding layer to increase the thickness of the flakes. The existence of H 2 Ti 2 O 5 , molybdenum disulfide and silicon dioxide is confirmed by X-ray powder diffractometer (XRD) and Fourier transform infrared spectroscopy (FT-IR). The prepared product was confirmed by XPS, BET test and electrorheological rheometer. Core/shell nanoparticles not only exert the active response characteristics of titanate nanoparticles and molybdenum disulfide to electric field, but also inherit the excellent characteristics of a core-shell structure produced by the interface polarization and the synergistic effect of the polar groups on the surface of the two-dimensional material further enhance the electrorheological effect. [ABSTRACT FROM AUTHOR]

Space charge accumulation is the main factor in accelerating the degradation of polymeric insulation in high-voltage direct current (HVDC) cables. It is essential for the development of HVDC cables to suppress the space charge in the insulating layer. In this paper, an approach is presented to decrease carrier injection from the inner semiconductive layer to the insulating layer, using a magnetic semiconductive compound. The semiconductive shielding compound was prepared by adding strontium ferrite to a carbon black/ethylene-vinyl acetate/low-density polyethylene (LDPE) matrix. The addition of strontium ferrite led to an increase in the residual magnetic induction of the semiconductor shielding layer. Unmagnetized and magnetized semiconductive compounds were used as electrodes to test the injection of carriers into the LDPE insulation layer. When SrFe12O19 had been added, the charge injected into the LDPE by the magnetized semiconductive layer was less than with an unmagnetized semiconductive layer. When the content of SrFe12O19 was 5 wt. %, 10 wt. %, 30 wt. %, and 50 wt. % in the semiconductive compound, the charge in the LDPE was reduced by 4.2%, 8.1%, 12.5%, and 27.1%, respectively. [ABSTRACT FROM AUTHOR]

• NiCoP/CNT nanoarrays and CNT@N-C nanoarrays were synthesized to construct flexible all-solid-state hybrid supercapacitor. • NiCoP/CNT can deliver a specific capacitance of 261.4 mAh g−1. • CNT@N-C exhibits a high capacitance of 256 F g−1. • The hybrid supercapacitor shows the maximum energy density of 138.7 Wh kg−1 and a power density of 6.25 kW kg−1. The exploration of flexible supercapacitors with high energy density is a matter of considerable interest to meet the demand of wearable electronic devices. In this work, with carbon nanotubes (CNTs) grown on carbon cloth (CC) as flexible substrate, NiCoP nanoflake-surrounded CNT nanoarrays (NiCoP/CNT) and N-doped carbon coated CNT nanoarrays (CNT@N-C) were synthesized on CC and utilized as cathode and anode materials for constructing flexible all-solid-state hybrid supercapacitor. Both them exhibit excellent electrochemical performance. NiCoP/CNT/CC composites can deliver a specific capacitance of 261.4 mAh g−1, and CNT@N-C/CC exhibits a high capacitance of 256 F g−1 at the current density of 0.5 A g−1. The hybrid supercapacitor built from the two well designed electrodes can provide a specific capacitance of 123.3 mAh g−1 at current density 1 mA g−1 within a potential window of 0–1.5 V and retain almost 85% of its initial capacitance after 5000 cycles. Furthermore, the flexible devices show the maximum energy density of 138.7 Wh kg−1 and a power density of 6.25 kW kg−1, obviously superior to some recent reported supercapacitor devices, indicating its potential in practical application. [ABSTRACT FROM AUTHOR]

TiO 2 nanoboxes with a hollow interior space, derived from titanium oxydifluoride (TiOF 2) nanocubes, were prepared using a two-step method, in which the TiOF 2 nanocubes acting as the precursor were first synthesized using a typical hydrothermal route. Subsequently, a second hydrothermal step was developed to prepare the TiO 2 nanoboxes. The clear phase transformation from the TiOF 2 precursor to anatase TiO 2 was confirmed using X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photo-electron spectroscopy analyses. The evolution of the morphology from a nanocube to nanobox was revealed by scanning electron microscopy and transmission electron microscopy observations. The influences of the phase and morphology on the electrorheological (ER) effect were investigated using an ER test. The ER results suggested that the ER efficiency was significantly enhanced after the second hydrothermal treatment, especially under a high external electric field strength. The enhancement in the ER efficiency was further studied using a dielectric spectrum analysis. It demonstrated that the faster response time and large permittivity difference obtained from the dielectric spectrum of TiO 2 were responsible for the improvement in the ER effect. [ABSTRACT FROM AUTHOR]

In this paper, titanium and tungsten films were coated on copper sheets, respectively, by plasma chemical vapor deposition (PCVD). The copper sheets before and after coating were, respectively, injected as charge into the low-density polyethylene (LDPE), the space charge accumulation in LDPE was tested by the thermally stimulated current (TSC), and the trap level of the dielectric was calculated by the TSC curve. The results show that the work function improves after the modification of the electrode material, the space charge accumulation in LDPE decreases, and the trap level of the polymer reduces. Because of the oxygen vacancies, the titanium coating electrode has significant suppression on the charge injection in LDPE under 30 kV/mm and the tungsten shows excellent inhibition under 70 kV/mm. [ABSTRACT FROM AUTHOR]

[Display omitted] • The artificial damp simulation experiments were conducted in different acidic and alkaline environments. • The physicochemical and electrical properties of XLPE and SIR specimens are evaluated. • Strong alkali has the strongest corrosive effect on specimens, with the most severe degradation of electrical properties. • The Material Studio is used to simulated the effect for electrical properties of breakage molecular chain. The insulation performance of the cable accessories is critical to the safe operation of the power grid. The environment in which the distribution cables are laid affects the insulating properties of the cable accessories. In this paper, the artificial damp simulation experiments were conducted in different acidic and alkaline environments. The physicochemical and electrical properties of specimens were evaluated. The patterns and laws of volume resistivity, breakdown strength, and surface flashover behavior before and after etching were investigated. The results indicated that the resistivity of specimens declined gradually with the extent of etching time. After 28 days, the resistivity of XLPE etched in strong acid (pH = 1) and strong alkali (pH = 13) solutions dropped rapidly, and the SIR decreased by 34.2% (pH = 1) and 26.5% (pH = 13), respectively. The breakdown strength of the two specimens exhibited an overall trend of decline. The XLPE was reduced by 19.08% (strong acid), and 20.61% (strong alkali), respectively, and the SIR was reduced by 15.59% and 17.50% after 28 days compared to the untreated specimens. The flashover voltage of SIR is more severely reduced than that of XLPE. The patterns and principles of the influence of acidity and alkalinity and ion concentration on the electrical properties of the specimens were discussed based on the experimental results. The work has an important guideline for the moisture-proof material selection and damp fault analysis of the cable accessories. [ABSTRACT FROM AUTHOR]

[Display omitted] • Improve the space charge injection characteristics of insulating layer by modifying the semiconducting layer. • Change the charge migration path by the action of the Lorentz force in the semiconducting layer. • Semiconducting layer composites with various particle sizes (SrFe 12 O19, from 80 nm to 1000 nm). • Concern the matching characteristics of semiconducting layer. and insulating layer. The key problem limiting the development of high-voltage direct current (HVDC) cable is the space charge accumulation within the insulation layer. A method is proposed to reduce the accumulation of space charge of cable insulation by a semi-conductive layer modified by magnetic particles. The physical essence is to change the charge migration path by the action of the Lorentz force in the semi-conductive layer. SrFe 12 O 19 particles with different particle sizes from 80 nm to 1000 nm are prepared by the sol-gel self-combustion method. The magnetic properties and resistivity of the semi-conductive layer composites with various particle sizes are investigated. In addition, the effect of the semi-conductive layer electrode for charge accumulation in the insulation layer is studied. Finally, the relationship among SrFe 12 O 19 particle size, magnetization intensity of the semi-conductive layer, and charge inhibition effect of the insulation layer is analyzed. The results of the experiments demonstrate that residual magnetization of magnetic particles has a significant impact on the space charge suppression. When SrFe 12 O 19 particle size is 200 nm, the charge inhibition effect is the best. This work can provide a new view for the charge suppression of insulation layer. [ABSTRACT FROM AUTHOR]

In this work, an atomic-layer-deposited Al2O3-induced LDH growth strategy was proposed to easily prepare carbon fiber-supported ultrathin CuAl LDH nanosheets (CF@CuAl-LDH). The uniform Al2O3 coating on carbon fiber (CF) was obtained using an atomic layer deposition (ALD) method and was used as a pinpoint inductive layer to transform into ultrathin CuAl LDH nanosheets through hydrothermal treatment. The LDH nanosheets grew densely attached to the CF surface and the nanosheet thickness was only about 3.3 nm. The obtained CF@CuAl-LDH exhibited superior enzyme mimic activity because its unique structural features offered a large ion-accessible surface, an increased active site area, and efficient electron-transfer pathways. Accordingly, a simple and sensitive biosensor was developed for colorimetric determination of H2O2 and glucose. The established method was successfully used to detect glucose in juice samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Abstract Engineering MoS 2 catalysts with more active sites and higher conductivity is an effective way to improve its electrochemical activity. Herein, defect-rich amorphous MoS x /carbon nanofiber (CF) arrays on carbon cloth (CC) support (denoted as MoS x /CF/CC) was designed and fabricated, which served as an efficient free-standing electrocatalyst for hydrogen evolution reaction (HER) in acid media. This architecture was beneficial to expose more active catalytic sites and improve the electron/ion transport. In addition, abundant defects altered preferred growth direction of MoS x , resulting in the formation of irregular MoS x particles at the surface of CF arrays. The as-synthesized MoS x /CF/CC-2 exhibited excellent stability and superior HER activity, with a small onset overpotential (107 mV) and low Tafel slope (51 mV dec−1). Such excellent electrochemical performance was attributed to the enriched active sites and shortened charge diffusion distance. This work would pave a new way for rational design and fabrication of defect-rich MoS x -based composite electrode for renewable energy applications. Highlights • Defect-rich MoS x /carbon nanofiber arrays on carbon cloth support were fabricated. • Abundant defects altered preferred growth pattern of MoS x. • Defect-rich MoS x could provide more active sites to promote the HER performance. • Carbon nanofiber/carbon cloth was a supporting material for defect-rich MoS x. [ABSTRACT FROM AUTHOR]

Flower-like TiO 2 @MoS 2 nanocomposite with a hierarchical and core@shell structure was synthesized using a two-step hydrothermal method, in which the flower-like Ti-containing precursor backbone was initially prepared to provide a large surface to enable the MoS 2 sheets to coat on TiO 2 uniformly. The glucose and acetate ion (Ac −1 ) were found to play a crucial role in the formation of the intimate interface between TiO 2 and MoS 2 . The hierarchical composite was dispersed in silicone oil as ER fluids at 10 wt%, which exhibited a high ER efficiency by combining the advantages of TiO 2 hierarchical structures and suitable conductivity of MoS 2 sheets. The high polarization strength and suitable dielectric relaxation of ER fluid was obtained under electric fields, which leaded to the improvement of interfacial polarization and ER activity. [ABSTRACT FROM AUTHOR]

We fabricated a clip-like polyaniline (PANI) nanofiber by using an insitu chemical oxidative polymerization assisted with a surfactant mixed system. First of all, three kinds of surfactants (cetyltrimethyl ammonium bromide (CTAB), polyvinyl pyrrolidone (PVP), sodium dodecyl benzene sulfonate (SDBS)) were used to provide different mixing combination. The combination of different surfactants has an important role on the morphology of obtained PANI nanoparticles. We propose possible synthetic mechanisms which CTAB and PVP as a structure directing agent plays the role of template to adjust the morphology. The morphology of clip-like PANI nanofibers has been characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure was characterized by X-ray powder diffraction, transform infrared spectroscopy (FTIR) and Thermo Gravimetric Analyzer (TGA). Moreover, the electrorheological (ER) behavior of clip-like polyaniline nanofibers was characterized by rotational rheometer. [ABSTRACT FROM AUTHOR]

One of the effective strategies to enhance hydrogen evolution reaction (HER) performance is to increase the catalytic sites of catalyst by designing and tailoring the nanoscale morphology of the catalyst. In this work, by using solid Co-glycerate (CoG) nanospheres as sacrificial template, various CoG hierarchical structures were successfully fabricated in water/ethanol mixed solution via a solvothermal reaction. The microstructure and morphology of obtained CoG nanospheres could be simply tuned by varying the water content. After a subsequent phosphorization reaction, multi-structural CoG was converted into hierarchical CoP nanospheres with well-preserved morphology. The essential influence of water on the microstructure of CoG was discussed in detail. Owing to the ultrathin nanosheet subunits, the as-prepared CoP nanospheres exhibited high performance with overpotential of 121 mV to achieve the current densities of 10 mA cm −2 , small Tafel slope of 56 mV dec −1 , and good stability under acidic condition. This work could provide an effective strategy to fabricate metal phosphide electrocatalysts with delicate hierarchical nanostructure for the application of HER. [ABSTRACT FROM AUTHOR]

MOF-Ti@PANI core–shell nanoparticles was synthesized using a two-step method. An electrorheological fluid with a concentration of 10w% was prepared by using MOF-T@PANI-0.2 as the dispersed phase, which can exhibit smart electrorheological behavior under external electric field. [Display omitted] • MOF-Ti@PANI core–shell nanoparticles obtained. • The special anisotropic shape, core/shell structure, and nanometer particle size was combined. • Smart electrorheological behavior exhibited obviously. • Large surface area and small pore size bring good interfacial polarization ability. In this paper, a kind of core–shell composite nanoparticles for electrorheological (ER) fluid was successfully prepared and showed good ER effect. The material possesses the high specific surface area and low density of metal organic frameworks (MOFs), and combines with the excellent dielectric properties of polyaniline (PANI). PANI precursors were prepared by a rapid mixing method, and then MOF-Ti (an MOF containing Ti) grew in situ on PANI under the solvothermal conditions. The MOF-Ti@PANI composite nanoparticles with core–shell structure were generated. These characteristics of PANI and MOF-Ti are conducive to stronger interfacial polarization of nanoparticles, which in turn leads to a good ER effect. The nanoparticle morphology as well as its ER and dielectric properties was modulated by using different amounts of PANI addition. The addition amount of PANI had a certain effect on the particle morphology, which was proved by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We also determined particle size at the nanoscale in this process. The measured results of the X-ray powder diffractometer (XRD) are consistent with the characteristic peaks of MIL-125 (a kind of MOF-Ti). The internal chemical structure of the material and the chemical environment of the elements were analyzed using Fourier infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Finally, the ER and dielectric properties of the nanoparticles in ER Fluids were investigated using high-speed rotational rheometry and broadband dielectric spectroscopy. The analysis revealed that the MOF-Ti@PANI core–shell nanoparticles have good ER properties under proper coating. For the core–shell modified MOFs, it is expected to be a promising development direction in the field of ER materials. [ABSTRACT FROM AUTHOR]

Anisotropic titanium oxide/polyaniline core/shell nanocomposite was synthesized via a three-step method, and its electrorheological (ER) properties under external applied electric field were researched. Firstly, monodispersed amorphous titanium oxide nanospheres were prepared by a controlled hydrolysis method and then anisotropic titanium oxide peanut-like nanospheres was obtained by using weak acid to etch the monodispersed titanium oxide sphere. At last, the surface of anisotropic TiO 2 was coated with polyaniline (PANI) through an in-situ polymerization method. Then the influence factors on the preparation of anisotropic TiO 2 /polyaniline core/shell structure nanoparticles were discussed deeply, including different kinds and amounts of acid, the amount of aniline, and so on. The morphology and structure of the samples were characterized by scanning electron microscopy, transmission electron microscopy, zeta potential analysis and X-ray powder diffraction, respectively. The electrorheological behaviors of the anisotropic TiO 2 /polyaniline composite particles are characterized using a rotational rheometer, which shown a good ER activity. [ABSTRACT FROM AUTHOR]

Cubic-like TiOF 2 @SiO 2 core–shell nanoparticles was synthesized by a two-step method as shown in the figure. The material exhibits smart electrorheological behavior under external electric field. [Display omitted] • cubic-like TiOF 2 @SiO 2 core–shell nanoparticles obtained. • The special unisotropic shape, core/shell structure, and nanometer particle size was combined. • Smart electrorheological behavior exhibited obviously. In this work, TiOF 2 @SiO 2 cubic-like core/shell nanoparticles was prepared using a simple two-step method. The cubic-like Ti-containing precursor is initially prepared via a template-free solvethermal method to provide a huge surface for the coating uniformly with the SiO 2 by a next hydrolysis. Through Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and element mapping, the surface morphology and structure was exhibited. The X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR) and X-ray photoelectron spectroscopy (XPS) can test the component, elements, as well as functional groups. And the ER effect at diverse electric field strengths is tested by a HAKKE rotating rheometer. According to the result, it can be concluded that the coating of SiO 2 can decrease the leaking electric current density and increase the shear stress, which makes the special cubic-like TiOF 2 @SiO 2 core/shell nanoparticles become a promising ER material. [ABSTRACT FROM AUTHOR]

1 A 2D nanomaterial (BNNSs) was used to develop large-scale production of high performance dielectrics. 2 PP-g-MAH is a good compatibilizer that can benefit the dispersion of the BNNSs. 3 Polypropylene/maleic anhydride-grafted polypropylene/boron nitride nanosheet ternary system nanocomposites were successfully prepared. 4 The maximal discharge energy density of 4.11 J cm−3 was achieved in 1%-BNNSs/PP/PP-g-MAH nanocomposites. With the development of advanced power system, high energy storage polymer film capacitors have attracted more and more attention. Polypropylene (PP) membrane is the most commonly used polymer based membrane, accounting for 70% of the total market share of products. Due to its low dielectric loss, it has a high charge-discharge efficiency (η). However, its inherently low dielectric constant (2.2 at 1 kHz) seriously hinders the increase of energy storage density (1–2 J/cm3). In this study, a ternary PP nanocomposite are prepared by melting blending and die pressing crosslinking, which greatly improved the capacitive properties of PP films. The discharge energy density (U e) of PP nanocomposite films increased from 1.63 J/cm3 to 4.11 J/cm3 by adding a small amount (1 wt%) of BNNSs into PP matrix. U e increased significantly (152.1%). By utilizing the special layered structure provided by BNNSs, the energy storage capacity of PP/ PP-g-MAH /BNNSs is significantly improved. [Display omitted] [ABSTRACT FROM AUTHOR]

It is still a great challenge to develop epoxy resin/glass fabric (EP/GF) composites with well-balanced enhancements on flame retardancy and mechanical properties. Herein, a novel strategy that polyhydric SiO 2 coating assistant to graft organophosphorus (DOPO) onto GF was developed for simultaneously improving flame retardancy and mechanical properties of EP composites. The grafting amount of DOPO could reach to 43.64 wt% via the helpful bridging of polyhydric SiO 2 , so that EP composites displayed excellent flame retardancy with the LOI of 37.2%, the V0 rating on UL-94 and a 63.3% decrease on PHRR in cone calorimeter test. According to the analysis of char morphology and structure, the flame retarded mechanism was mainly ascribed to the enhanced barrier effect of a continuous and intergrow char layer, which was composed of GF@SiO 2 as framework and P-containing condensed carbon as stuffing. Meanwhile, EP composites exhibited outstanding mechanical performances with 35% and 60% increases on tensile strength and impact strength respectively, which resulted from the special molecular structure of GF@SiO 2 - g -DOPO with strong interfacial adhesion with EP chains via hydrogen bond and chemical bond. In summary, this work will be favorable to design multifunctional polymer composites with well-balanced comprehensive performances, and expand their widespread applications in high-end fields. [Display omitted] • A novel polyhydric SiO 2 coating assistant to graft organophosphorus onto GF. • The grafting amount of DOPO could reach to 43.64 wt%. • Excellent flame retardancy with LOI of 37.2%, V0 rating on UL-94 and a 63.3% decrease on PHRR. • Outstanding mechanical performances with 35% and 60% increases on tensile strength and impact strength respectively. • The corresponding enhancement mechanisms on flame retardancy and mechanical performances were revealed. [ABSTRACT FROM AUTHOR]

Abstract： Flower-like Fe 2 O 3 /polyaniline core/shell nanocomposite was obtained via a two-steps method. Firstly, monodispersed flower-like iron oxide was synthesized by a high temperature refluxing method. Then flower-like Fe 2 O 3 /polyaniline core/shell nanocomposite was further obtained via the in-situ polymerization. Scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), SQUID MPMS, UV–vis and Haake rheometer were used to investigate its structure, morphology and properties. The obtained Fe 2 O 3 /polyaniline nanocomposite reveals an interesting morphological combination of hierarchical and core/shell structure. Its electrorheological (ER) behavior were investigated using a rotational rheometer under different applied electric field strengths when dispersed in silicone oil, which shown an obvious ER activity. [ABSTRACT FROM AUTHOR]

Hollow polyacene quinone radical (PAQR) submicrospheres are synthesized by a modified solvothermal method. The morphology and structure of the hollow PAQR submicrospheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and Haake rotational rheometer, respectively. Meanwhile, both the size and the shell thickness of PAQR hollow submicrospheres could be adjusted by changing the amount of surfactant-sodium dodecyl sulfate (SDS). When PAQR hollow submicrospheres are used as the electrorheological (ER) dispersed materials, good ER effect is achieved. Furthermore, the hollow structure is beneficial to improve the anti-sedimentation property for ER application. [ABSTRACT FROM AUTHOR]

Poly(p-phenylenediamine)/graphene oxide nanoplatelet (PPDA/GONP) composites were synthesized via in situ oxidation polymerization of p-phenylenediamine (PDA) in graphene oxide nanoplatelets (GONPs) suspension for potential electrorheological (ER) fluid applications. Initially, the mass production of GONPs can be achieved through a simple and green ball milling process of graphite with dry ice. The versatile synthesis methods and multifunctionality of poly(p-phenylenediamine) (PPDA) enable the wide potential applications of PPDA/GONP composites. The π−π stacking interaction between GONP and PDA is a key factor to fabricate PPDA/GONP composite successfully. The ER characteristics of both PPDA/GONP composites and PPDA in silicone oil medium were examined using a rotational rheometer equipped with a high voltage generator. The resultant PPDA/GONP composites exhibited improved typical ER behavior compared with that of pure PPDA, providing a new potential application of the PPDA/GONP composites as an intelligent material. [ABSTRACT FROM AUTHOR]

α-Fe2O3@TiO2 core-shell nanoparticles were prepared through a combination of reflux and hydrolysis methods. Firstly, a spindle-like and monodispersed α-Fe2O3 nanorod core was fabricated by using a reflux method. In the second step, an amorphous TiO2 shell was coated onto the surface of the nonspherical α-Fe2O3 core with a uniform thickness by means of a controlled hydrolysis method. The morphology, structure, and electrorheological (ER) activity of α-Fe2O3@TiO2 core-shell nanoparticles were determined by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), magnetic testing, and by using a rotational rheometer. The resulting nonspherical core-shell nanoparticles possess the advantages of uniform sizes, weak magnetism, and smart electrorheological behavior. An enhanced ER effect is found with the α-Fe2O3@TiO2 and hollow TiO2 ER suspension compared with that of a pure α-Fe2O3 ER suspension. [ABSTRACT FROM AUTHOR]

A series of Cr-doped multiferroelectric FeBiO 3 nanoparticles were synthesized via a facile sol gel method. The resultant Cr-doped FeBiO 3 was characterized by means of different techniques, such as scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and electrorheological (ER) tests. Under an external electric field, electrorheological properties of the suspension containing such Cr-doped and undoped FeBiO 3 particles were investigated by steady shear experiments. It was found that the suspension of Cr-doped FeBiO 3 particles possesses a better ER effect than that of pure FeBiO 3 particles. Furthermore, different Cr-doped concentration plays an important role on the ER behavior. Combining the dielectric analysis, the enhanced ER effect of Cr-doped FeBiO 3 suspension can be attributed to the improved interfacial polarization. [ABSTRACT FROM AUTHOR]

TiO 2 supported anisotropic C 3 N 4 rod-like composite was synthesized, and be used as a dispersed material for new type electrorheological fluid. By applying electric field to the C 3 N 4 /TiO 2 based electrorheological fluid, it is found that as-obtained C 3 N 4 /TiO 2 suspension shown a strong yield stress and significant switching effect. C 3 N 4 /TiO 2 nanocomposite with rod-like and core@shell structure was synthesized using a two-step method, which can exhibit stronger electrorheological behavior under external electric field. [Display omitted] • Rod-like core-shell structure C 3 N 4 /TiO 2 obtained. • Smart electrorheological behavior exhibited obviously. • The dielectric properties of C 3 N 4 /TiO 2 ERF is investigated. [ABSTRACT FROM AUTHOR]

Abstract: Thermoplastic vulcanizates (TPVs) based on high density polyethylene (HDPE)/ethylene–propylene diene copolymer (EPDM) blends with different compositions of polyethylene–octene elastomer (POE) were prepared by dynamic vulcanization, the effects of the POE incorporation on deformation reversibility enhancement, mechanical, dynamic mechanical and morphological properties of the TPVs were investigated systematically. Characterization via FE-SEM confirms the tearing strips on the fracture surface of HDPE/EPDM TPVs were formed by the residual plastic deformation of HDPE lamellae crystals, which also resulted in the relatively high permanent deformation of TPVs. The elasticity of TPV matrix was improved greatly by the incorporation of POE and the tension set was decreased obviously. RPA results show that the increasing frequency led to the increased elastic modulus while the incorporation of POE in matrix led to the decreased elastic modulus. The tan δ decreased continuously with the increasing frequency and the incorporation of POE had a non-ignorable influence on the tan δ of HDPE/EPDM TPVs. [Copyright &y& Elsevier]